ZENITH Solidifies its Worldwide standing because the main manufacturer of precision chronometers and devices across quite a few domains. The 3rd big stage took place within the early 1900’s. The shape from the timekeeping equipment adjusted in favor of your wristwatch. The 1st chronometer wristwatch movement came in about 1910, https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/